PLATE 27. 



The Granville tobacco-wilt, a bacterial disease. 



The left-hand plant wilted naturally in the field, was pruned, transplanted to the hothouse, recovered for a few weeks, developed the leaves shown, and then wilted again. 

 Photographed June 28; one-thitd natural size. 



In this disease the vascular ring is browned and cavities are formed in the stem. The bacterial slime is gray-white and abundant. Fungi were not present in the plants 

 examined hy me. Poured plates were made from the interior of several such stems, and these yielded practically pure cultures of one organism. A subculture from one 

 of these colonies was used to inoculate the right-hand plant. The needle-pricks were made on July 13, 1905. Photographed August 3; one-half natural size. Twelve 

 plants were inoculated at this time and all contracted the disease. The signs and lesions were the same as in the plants obtained from the field. The organism causing 

 this disease is closely related to Bact. solanacearum. 



